Zogby’s chief concern—raised by several other current DNC members who spoke with The Daily Beast—is that the Trump campaign is already reaching swing voters while the Democratic Party is overwhelmingly focused on expanding their existing base.
It's one of the reasons a sitting POTUS is very hard to beat. They are running primaries and have to get their base to the polls just to get the nomination. Trump has done a beautiful job of marginalizing all of them so whoever does get the nomination is really handicapped.
I'm not buying the polling either. After what Trump has been able to get done with little or no help how can he not be re-elected.